1. Field of the Invention
The present invention relates to a CD-ROM (compact disc read only memory) reproducing apparatus for reproducing a CD-ROM disc on which information such as dictionaries, encyclopedias, road maps, etc., are converted into digital data and recorded on the basis of a compact disc format.
2. Description of the Relevant Art
One conventional optical disc on which publications such as dictionaries, encyclopedias, road maps, etc., are optically recorded as digital data on the basis of a compact disc format is generally referred to as a CD-ROM disc. The CD-ROM discs are recently popularized and receive remarkable attention because a vast number of pages can be recorded on one CD-ROM disc. CD-ROM disc is an optical disc which permits an easy random access and the CD-ROM disc can be reproduced in a non-contact fashion to guarantee a semi-permanent life, etc.
Because the physical characteristics (size, optical characteristics, track pitch, modulation method, etc.) of the CD-ROM disc are in accordance with the CD (compact disc) format, a mechanism of the CD-ROM disc reproducing apparatus serve also as that of a CD player. Therefore, a player that can play both the CD-ROM disc and the CD can be provided by a minor modification such as the addition of a data decoder exclusively used for the above CD-ROM player. The conventional CD-ROM disc reproducing apparatus can search for desired information from the CD-ROM disc loaded thereon and display the desired information thus searched on a display apparatus. The conventional CD-ROM disc reproducing apparatus, however, cannot display the previously-searched retrieved information on the display apparatus when the former CD-ROM disc is changed to another CD-ROM disc. Whenever the user wants to see the same information frequently, the user must change the CD-ROM disc into another one on which such desired information is recorded, which is very cumbersome for the user. Also, when related information is recorded on different CD-ROM discs, the successive CD-ROM discs must be loaded onto the CD-ROM disc reproducing apparatus alternately, which requires excess time for the user to make good use of information recorded on the CD-ROM discs.